Presser foot for sewing machines



June 30, 1942. KAHRE 2,288,404

PRESSER FOOT FOR SEWING MACHINES Filed Oct. 2'7. 1939 Patented June 30,1942 UNITED STATES PATENT OFFICE 11 Claims.

This invention relates to improvements in a presser foot for sewingmachines for felling seams and pertains more particularly to means foradjusting the foot when necessary to provide for both sides of thefabric material at the seam, to flow out evenly at the finish, thisbeing a primary object of the invention.

In the use of the present form of presser foot in garment factories, itis seldom that two bundles of seamed articles are run out alike becauseof the unevenness of the material adjacent the seam, and consequently itis necessary to stretch one side of the material at the seam to makethat side even. To avoid this in the use of the present form of presserfoot, the operator has to pull on the uneven side of the material andstretch it to an extent whereby it will finish out even during theseaming operation, and quite often this stretching is repeated even whenthe seam is completed. This stretching often causes the sewing machineto chew and make a very irregular stitch as well as causing the fabricmaterial to slip under the presser foot and cause bending of the needlesand in some instances the needles are at times broken. The invention ofthis application is therefore capable of overcoming this difficulty.

Another object of the invention is to provide a presser foot with meansfor adjusting the tension of the fabric engaging parts thereof.

A further object is to provide a presser foot with means which arecooperable with the fabric engaging part or parts thereof, to disposethe parts into more or less effective contact with the fabric as may berequired with respect to the feed dog of the sewing machine.

Another object is to provide each fabric engaging section of a presserfoot with adjustable means.

With the foregoing and other objects in view which will appear as thedescription proceeds, my invention resides in the combination andarrangement of parts and in the details of construction hereinafterdescribed and claimed, it being understood that changes may be madewithin the scope of what is claimed without departing from the spirit ofthe invention.

An embodiment of the invention is illustrated in the accompanyingdrawing, wherein:

Figure 1 is a side elevation of a fragmentary portion of the presserfoot end of a sewing machine showing my improvements applied thereto.

Figure 2 is a plan view partly in section taken approximately on theline 22 of Fig. 1.

Figure 3 is an elevation of the opposite side of the presser foot shownin Fig. 1.

Figure 4 is a longitudinal sectional elevation taken approximately onthe line 4-4 of Fig. 2, through the presser foot.

Figure 5 is a transverse vertical sectional elevation takenapproximately on the line 55 of Fig. 1.

Figure 6 is an enlarged transverse vertical sectional elevation takenapproximately on the line 66 of Fig. 1.

In the drawing, the sewing machine is shown as including a supportingbase 8 which extends upwardly in the form of a standard 9 having aneedle head I0 carried by an over-hanging portion of the standard and awork supporting arm II which is extended from the standard. A needle barI2 carrying a set of three needles lZa reciprocates in the needle headI0.

Mounted on the work supporting arm II is a folder I3 of the usual typeand disposed in said arm is a feed dog I4 having fabric engagingsections I5 and I6. The machine as shown, is of the type illustrated inChristensen et al., U. S. Patent 1,741,095, and further description ofthe machine is not thought necessary.

The presser foot I! consists of a front section I8 and a rear section I9which are disposed in tandem above and in proximity to the feed dog I I,the front section III being pivoted on one side at 20 to an arm 2| of ayoke 22 and on its other side is pivoted at 23 to an adjustable bearing50.

' The rear section I9 of the presser foot is pivoted on one side at 25to the arm 2| of the yoke 22 and on its other side is pivoted at 26 tothe arm 24, and the yoke 22 is in turn secured to the shank 21 by apivot 28 engaging the arm 2! of the yoke and the shank, and a pivot 29engaging the arm 24 and an adjustable bearing 33.

The bearing 50 has an upwardly extending stem 3! which is seatinglyengaged in a tubular adjusting screw 32, said screw 32 having exteriorthreads 33 which engage interior threads formed in a boxing 34, securedto or formed integral with the arm 24 of the yoke 22.

The shank 21 is mounted on the lower end of the presser bar 35 which isdepended from the needle head I 0, said presser bar having the usualspring associated therewith which forces the presser foot I1 intoyielding contact with the fabric sections to be seamed.

The rear section I9 of the presser foot I! is provided with a channel 36and mounted therein is a shiftable plate 3'! which is fixed to the lowerend of a threaded stem 38 which passes through an opening in the section[9, and engaged on the threaded end of said stem is an adjusting nut 39which is held in adjusted position by the spring 49 which is secured tothe rear end of the section H) by the screw 41.

The shiftableplate 31 is adapted to yieldably engage the sewed orthreaded seam portion of the fabric immediately after the seam has beenstitched by the set of reciprocating needles lZa which operate throughrespective elongated openings E2 in the front section H! of the presserfoot IT. The channel 33 of the rear section IQ of the presser footprovides side disposed runners 43 and M thereon and runners 45 and G6are similarly formed on the front section M3 for cooperation with thefeed dog l4 on the fabric to be seamed.

Secured to or formed integral with the shank 21 is an interiorlythreaded boxing ll, and engaged therein is a tubular adjusting screwtill and seated in said screw the approximate length thereof, is a stem49 which extends upwardly from the bearing 38 which is pivotally mountedat 29 to the arm 24 of the yoke 22. Disposed on the outside of theboxing 47 is a resilient locking rod 5!, the extending end of whichcooperates with notches 52 which are formed in the periphery of a flangeat the upper end of the adjusting screw 58.

In operation, the material is drawn through the folder I3 and deliveredto the stitching mechanism of the sewing'machine by the feed dog l4having fabric engaging sections l5 and It. As best shown in Fig. 6, thefabric section 55 is folded over as designated at 56 and the fabricsection 51 is under folded as indicated at E3, and it is these foldedportions which are interengaged for the forming of the felled seam 59.These inter-folded parts of the fabric sections lie between the sectionsi5 and it of the feed dog is and are not engaged thereby, the mainfeeding of the fabric sections 55 and 5'1 being carried on bycooperation of the feed dog sections 55 and iii with respective runnersof respective sections it and is of the presser foot ll.

In the pulling or feeding operation of the feed dog on the material, itquite often happens that the seam does not run out evenly and whichdefect occasions the operator to hand stretch the material on one sideof the seam in order for the seam to finish out evenly and often afterthe seam is completed. During stretching of the material, this oftencauses the machine to chew and to make a very irregular stitch due tothe material slipping under the presser foot and which will causebending of the needles and often the needles are broken.

This invention therefore is adapted to overcome the defect of thematerial slipping during feeding, and causing irregular or uneven seamsby providing proper tension on both sides of the presser foot, one ofthe requirements being to first set the presser foot ll squarely on thematerial by manipulation of the screw :28 on the hearing 30 foradjusting the yoke which carries the front and rear sections it and isrespectively.

When slippage of the material during feeding occurs, which often is dueto the texture or grade of the material, the front section it whichembraces the needles !2a is adjusted by the operator manipulating thescreW 32 to force the bearing 58 downward to cause that side of thesection l8 carrying the runner 45 to more tightly bear against thefabric section 51 thereby pressing said fabric section firmly againstthe section It of the feed dog Hi, thus increasing the biting efficiencyof the feed dog on the fabric section 5i by reason of closer contact ofthe runner 46 thereon and causing the dog Hi to feed faster or to adegree wherein the material will flow or be fed more firmly beneath thepresser foot to obtain an even stitching and so that both sides of theseam will run out even at the finish.

At times when adjusting the front section it of the presser foot, it maybe found necessary to adjust the rear section if? by manipulation of thescrew G8 thereof against the bearing 30 to regulate the engaging contactof the runner id on the fabric section 5? to a degree as may berequired, by the amount of adjustment given to the front section E8 inorder to assure evenly alined feeding of the fabric sections which arebeing seamed.

The adjusting screw 32 of the front presser foot section It is alsoprovided with a resilient rod 53 for locking cooperation with thenotches 56 formed in the flanged end of the screw.

Obviously, retrograde turning of the adjusting screws 32 and 43 willaccordingly release the runner engaging pressure given to respectivesections I8 and [9.

In adjusting the sections it and IQ of the presser foot ii in the manneras described, sufficient tiltable movement for the adjustment isprovided by the pivots 20 and 28 of the yoke 22, it of course beingunderstood that the amount of adjustment required is relatively small.Relatively long bearing support for the stems 3! and E9 of respectivebearings and 39 is provided in respective tubular adjusting screws 32and 48 by reason of the relative lengths of said stems and adjustingscrews. The stems 3i and d9 of respective bearings 56 and EQ obviouslyin a sense, provide adjusting legs for respective fabric engagingsections l8 and i9.

What I claim is:

1. A presser foot for a sewing machine comprising a rockable yoke, afabric engaging section rockably secured to said yoke, and adjustablemeans carried by said yoke and having cooperable connection with oneside of said section,

2. A presser foot for a sewing machine having a ycke, a fabric pressingsection pivoted on one side to said yoke, and an adjustable bearingcarried by said yoke and pivoted to the other side of said section.

3. A presser foot for a sewing machine having a yoke, a fabric pressingsection pivoted on one side to said yoke, and a screw-adjustable bearingcarried by said yoke and pivoted to the other side of said section.

4. A presser foot for a sewing machine having a yoke, a fabric pressingsection pivoted on one side to said yoke, and an adjustable bearinghaving slidable connection with said yoke and having pivotal connectionwith said section in alinement with the pivot on the other side of saidsection.

5. A support for a presser foot section comprising a shank, a yokerockably secured on one side to said shank, and a bearing adjustablycarried by said shank and pivotally secured to said yoke.

6. A presser foot for a sewing machine having a shank, a yoke rockablysecured on one side to said shank and on its other side to an adjustableelement borne by said shank, and a fabric engaging section rockablysecured to said yoke.

'7. A presser foot for a sewing machine having a shank, an elementadjustably secured to said shank, a yoke rockably secured on one side tosaid shank and on its other side to said element, and a fabric engagingsection rockably secured to said yoke.

8. A presser foot for a sewing machine having a shank, an elementadjustably secured to said shank, a yoke rockably secured on one side tosaid shank and on its other side to said element, and a pair of fabricengaging sections carried by said yoke, one of said sections beingadjustably secured on one side to said yoke.

9. A support for a presser foot comprising a shank, a yoke havingpivoted bearing connection with said shank, said bearing connectionhaving a stem and a tubular screw element mounted thereover and saidscrew element being screwseated in said shank.

10. A presser foot for a sewing machine having a shank, a yoke rockablysecured to said shank, a fabric engaging section having pivotal bearingconnection with said yoke, said bearing connection having a stern, and atubular screw element borne by said yoke and mounted over said stem forproviding adjustment to said section.

11. A presser foot for a sewing machine having a shank, an elementadjustably secured to said shank, a yoke rockably secured on'one side tosaid shank and on its other side to said element, and a fabric engagingsection rockably secured to said yoke and having adjustable cooperationtherewith.

GEORGE. F. KAHRE.

